Electrical contactor



4 Sheets-Sheet 1 Filed March 7, 1949 Av v INVENTOR.

ATTORNEYS.

Sept. 1, 1953 P. v. YINGST ELECTRICAL CONTACTOR Filed March 7, 1949 4 Sheets-Sheet 2 INVENTOR.

S Y E N m? 5 T g T .m A Y? M w G I P Sept. 1, 1953 P. v. YINGST 2,650,966

ELECTRICAL CONTACTOR Filed March 7, 1949 4 Sheets-Sheet 3 & Paul V' Yingst ATTORNEYS.

Sept. 1, 1953 P. v. YINGST ELECTRICAL CONTACTOR 4 Sheets-Sheet w m QEQR Filed March 7, 1949 F GE INVENTOR.

ATTORNEYS.

Patented Sept. 1, 1953 UNITED STATES PATENT OFFICE Post-Glover Electric Company,

Ohio, a corporation Cincinnati,

Application March 7, 1949, Serial No. 79,997

flCla-ims. 1

This invention relates to improvements m electrical contactors and electrical systems.

The primary object of this invention is the provision of a direct current accelerating contactor of the single or double pole type embodying structural features set forth in U. 'S. Patent 2,632,822, dated March 24, '1953, more particularly directed to use as an accelerating contactor in connection with direct current motor control; the same being particularly well adapted for use in connection with the forward and reverse driving of a motor, and capable of supplying the control features of a reversing magnetic motor starter for either direction of rotation.

A further object of this invention is the provision of an improved accelerating contactor of the single or double pole type having associated therewith ashunt type holding coil for delaying energization of the motor for rotational change in direction, until the motor has reduced in speed so that the CEMF has reached a predetermined low percentage of rated voltage.

A further object of this invention is the provision of an improved accelerating contactor having associated therewith'a main current controlling switch having electromagnetic operating means therefor including an armature, and a motor armature controlled holding coil associated in complementary relation with the armature of the switch, and further having associated therewith a normally closed auxiliary contact.

A further object of this invention is the provision of a contactor having the parts so constructed and arranged that the movable connection of all relatively movable parts is located close to the base panel for purposes .m'ore specifically enumerated in my Patent 2,632,822.

Other objects and advantages of this invention will be apparent from the following detailed description.

In the accompanying drawings, forming a part of this specification, and .wherein similar reference characters designate corresponding parts thruoutthe several views Figure 1 is a plan view or the improved accelerator contactor, showing a double pole itype.

Figure 2 is a side elevation of the contactor of Figure 1.

Figure 3 is a longitudinal cross sectional view taken thru the contactor substantially Jon the line 33 of Figure 1.

.Figure 4 isan elevation of the double ,pole type contactor, taken from the holding coil .end thereof.

Figure 5 is a cross sectional view taken substantially thru .the double pole type contactor substantially on the line 55 of Fgure 1.

Figure 6 is a cross sectional View taken thru the main switch controlling coil, holding coil and .the common armature for said coils; the view being taken substantially on the line .6 6 of Figure ,1.

Figure '7 is a plan view of a single pole type of accelerating contactor.

Figure 18 is a crosssectional view taken through the terminal structure of the normally closed auxiliary contact assembly, substantially on the line '88 of Figure 9.

Figure .9 is a plan view of a normally closed auxiliary contact associated with the accelerator contactor.

Figure 10 'is a side elevation, partly in section, 3% the normally closed auxiliary contact assem- ."Figure 11 is a cross sectional view taken thru the contactor of Figure 7 substantially on the line I lf|l of Figure 7.

"In the drawings, wherein for the purpose of illustration are shown single pole and double pole types of accelerating contactors, the letter A may generally designate the double pole accelerat'ing contactor, and B the single pole accelerating contactor. They both embody similar constructions with the exception of the coil armature mounting.

"I nasfar as applicable, similar reference charactersd'esignate corresponding parts thruout the various views of both forms of contactors.

Each of .the accelerator contactors A and B includes a panel C having an improved contact arm structure -D adapted for proper cooperation with a contact 'E with which is associated an arc extinguishing means F. An electromagnetic coil *is provided, with which is associated an armatur'eHinthe 'form of accelerating contactor A, and an armature H in the form of accelerating "contactorB. With each of the forms A and B there is associated an improved holding coil structure K. Furthermore, there may be provided an auxiliary contact assemblage L, shown indetail'in Figures 8, 9 and 10 of the drawings which may be made apart of and associated with the holding coil in either the double pole .typeof accelerating contactor .or the single pole type of accelerating contactor.

The panel ,C isof a size and nature to coniorm torthepcapacity of the contactor and it may hepmvided with suitable apertures it for reoeiving mounting bolts. The base may be mount- 3 ed in vertical, horizontal or angular planes, as desired.

Referring to the contact arm construction D, the same preferably includes a cast aluminum rocker arm l5 of L-shaped formation. It coinprises a lower contactor arm connecting portion 56 and a right-angled armature connecting portion H. The arm !5 is provided with a barrel portion I8 adapted to receive from opposite sides thereof (Fig. 11) the reduced sleeve ends of oil-les type of sleeve bearings.

A cast aluminum rocker arm support or bracket 2! is provided, having a base portion 22, bolted as at 23 to the panel C, as shown in Figure 3. This bracket 2i includes wall portions 24 and 25 extending normal to the plane of the panel C for supporting a mounting pin or shaft 25 as shown in Figure 11. The mounting pin 25* has a head at one end and is secured by means of a cotter pin at its other end to the bracket structure, as shown. The flanged-type of oil-less bearing include, in addition to the sleeve portion 2|], the outer enlarged flange portion 28 which abut the inner surface of the bracket supporting walls 23 and 25.

To the under surface of the rocker arm portion it is secured, by bolts 30, a beryllium-copper spring arm portion of an inherent springy nature. With arm 35 is associated, as part of the contact arm, a laminated copper strip construction consisting of a plurality of copper strips 36. The parts 35 and 353 are connected to the rocker arm portion it by bolts or screws 30. At its end the contact arm is provided with a copper contact tip it which is silver inlaid. It covers the lower surface and the front edge of the arm and is provided with a screw threaded stud l! which extends thru the end of the berylliumcopper spring arm portion 35 and is secured thereto by means of a nut 52. The laminations 36 are provided with kinks defining an expansion loop 58. The beryllium-copper portion 35 terminates at the mounting sleeve portion iii of the rocker arm but the copper laminations continue around the portion it and extend upwardly for connection by means of a terminal bolt 52 to the rocker arm portion ii. This terminal bolt 52 also connects a conductor braid 53, the opposite end of which is connected to a binding post 54.

The copper contact E, which has a silver inlay tip, is mounted by means of a bolt til to the bight or base portion ti of a U-shaped permanent magnet comprising part of the arc blowout F. The copper-silver contact E is provided with a face which slopes slightly toward the plane of the panel E, as will be noted from Figure 3, for efficient contact engagement with the contact tip 463 of the contact arm. A connecting link 62 is clamped between the contact E and the base for conductor attachment with the binding post 64.

The U-shaped permanent magnet may be attached to the panel by means of screws, shown in dotted lines at 65 in Figure l of the drawings. It is to be noted that the surface engagement of contacts ll and E lies within the permanent magnet.

An insulation and heat dissipating shield i0 is detachably connected with the upstanding walls or flanges 'ii of the permanent magnet. It straddles the compartment wherein lie the contacts i0 and E and consists of a top wall l2, depending side walls 13 and a rear wall connecting lower portion '85. The walls are arranged to define a compartment, shown at 16, which opens forwardly. The shield ill has a passageway 11 for heat dissipation. The outer surfaces of the wall portion H are recessed for receiving the flanges ii of the permanent magnet and the shield is provided with spring clip attaching arms 19 secured at 89 thereto, th lower ends of which are stud-notched to frictionally engage in recesses (not shown) located on the outer surfaces of the flanged portions H of the permanent magnet. It is obvious that the shield may be readily pulled upward and detached from the permanent magnet to expose the contacts.

For the double pole type of contactor, the above contact arm and complementary arc blowout are duplicated, as shown in Figures 1, 4 and 5 of the drawings. They are located in complementary relation and the rocker arm portions I'd thereof support an insulation plate or panel 98, secured as by screws 9! thereto. The terminal braid connecting bolt 52 also aids in securing the insulation plate 98 in position and the insulation panel is reinforced by a metal strip or plate 92 to which the screws or bolts 52 are also connected, as shown.

The electromagnet includes a coil G mounted upon an axis which is parallel with the plane of the panel C and as close as possible to the panel. Mounting is made upon the outstanding wall portion 586 of a yoke or bracket, the bottom Or base m2 of which is attached by means of bolts its to the panel C. As i more clearly shown in Figure 6 of the drawings, the wall I00 of the yoke has attached thereto bolt Hi4 which extends into the core structure I05 of the coil. This efiiciently mounts the coil in stable position upon the panel.

The armature H, of the double pole type of connector, is connected by the bolts 9i, shown in Figures 1 and 4 to the reinforcing strip 92 and the insulation plate 9t.

Each of the contact arms for the single and double pole-types of contactor includes an improved spring arrangement, best shown in Figures l, 5 and 11 of the drawings which may appropriately be referred to as a double torsion type spring for th purpose of holding the contactor arm or arms open. These springs are centered on the pivot shafts of the respective contact arms. Each spring, designated at H0 in the drawings, includes a U-shaped portion the bight iii of which engages the exposed face of the rocker arm portion Ill and thence extends downwardly at an acute angle to the plane of the contact arm and terminates in coil spring portions H3 wrapped around the flanged parts 28 of the rocker arm bearing structures. The normal effect of the springs HE? is to hold the contact arms open with respect to the contacts E, and of course to move the armature away from the core.

The armature structure H for the single pole type of contactor switch shown in Figures 7 and 11, is provided with a sleeve portion I29 provided with a fixed pin i2i, the ends of which seat in sleeve type oil-less bearings I22 mounted in ears or bearing lugs I23 which are integral with the coil mounting yoke base HJZ shown in Figure 11.

The single and double pole accelerator contactors can be supplied with or without the arc blowouts above described.

Referring to the construction of the holding coil K, the armature structure H and H of the forms of invention A and B above described also serve as the armature for the holding or lockout magnetic path. The holding coil K is mounted upon a yoke I bolted as at 'I3I upon the panel structure C, as best shown in Figure 6. It has a holding circuit core 132 secured to the bracket or yoke I30 in an opening I34; a jamb nut I35 holding the adjustment. The holding coil K may be of either the series or shunt type, electrical connections being made thereto at the terminals 35. A thin nut and washer structure I31 secure the coil K in position upon the coil at the opposite end. It is quite apparent that the core 132 may be moved along its axis of the coil by loosening the nuts I35 and 31 for the purpose of varying the distance (air :gap) between the armature end of the coil I32 and the armature plate 92. The axis of the coil K is slightly on"? parallel with the plane of the panel, so the armature of the switch will lie in a plane normal to the axis of the coil K when in attracted or held position.

It is intended that the auxiliary contact structure L be selectively utilized in connection with either the single pole or double pole type switches. The mounting is shown in Figures 8, 9, l0 and 11.

To that end the top wall of the yoke I30 may serve as a support for the auxiliary terminals I and MI which are in the form of angle clips secured to insulation blocks I42 and I43 respectively. The terminal pieces I40 and [M are of copper or similar material and inlaid with silver on the contact surfaces thereof. The insulation mounting blocks I42 and I43 are secured to the bracket or yoke I30 by screws or bolts I45 screw threaded into openings on the top wall of the bracket I30 as shown in Figure 10.

A thin layer of insulation material I46 insulates the contacts from the holding circuit yoke I30. Screws I48 mount the terminal pieces I40 and MI in position, and the latter may be supplemented with angle clips for supporting binding screws I49 and I50, as shown in Figure 8.

The movable part of the normally closed auxiliary contact assembly is mounted upon the main armature H or H, as the case may be. To that end, as shown in Figures '7, 9, 10 and 11, the armature H is provided with a mounting opening 5I therein. A shorting bar I52 is provided, upon which contact points I52 and I52 are mounted for the contacts I40 and I4I above mentioned. The shorting bar I52 is provided with an opening thru which slidably extends a tube I54. A compression spring I55 is disposed between the armature H and the shorting bar I52 for holding the latter in forward position. The entire structure is mounted upon a detachable bolt I56.

Inasmuch as the springs III) normally throw the armature H and H to open position with respect to the electromagnetic coil G, it is quite obvious that the auxiliary contacts L are normally closed.

The accelerator contactor, merely by way of example, has a maximum capacity of 100 amperes per pole, 250 volts. Of course other sizes of similar construction can be made. They are adapted to operate on 80 to 110% rated voltage.

The improved accelerating contactors are used in connection with the forward and reverse drive of an electric motor. The single pole contactor of the type shown in form B allows the use of a starting resistor, starting the motor with a limited inrush current, and progressive step by step cut-out of the resistor as motor current varies between maximum and minimum as limited by the resistor. The minimum is determined by the adjustment of the core of the holding coil. A normally closed auxiliary contact in series with the shunt type holding coil is used only when full voltage would otherwise be applied to the holding coil during continuous operation. Since the holding coil of the contactor has no function during continuous operation, it need not be of the continuous type. Thus, the auxiliary contact is an added feature for such application, or for whatever purpose is found necessary.

Various changes in the shape, size and arrangement 'of parts may be made to the form of the invention herein shown and described without departing from the spirit of the invention or the scope of the following claims.

I claim:

1. In an accelerating contactor the combination of a supporting base, a main current controlling switch comprising a contact mounted upon the base and a contact arm pivoted upon the base on an axis substantially parallel to the base and close to the same, spring means normally throwing the contact arm to open position with respect to its contact, an armature pivoted upon the base on an axis common to the axis of the switch arm, said armature being connected to the switch arm for movement therewith, an electromagnetic coil mounted upon the base on an axis substantially parallel to and close to the base. and a holding coil for said armature mounted upon the base on an axis close to and non-perpendicular to the base and in armature attracting opposition with respect to the coil first mentioned.

2. In an accelerating contactor the combination of a supporting base, a main current controlling switch comprising a contact mounted upon the base and a contact arm pivoted upon the base on an axis parallel to the base and close to the same, spring means normally throwing the contact arm to open position with respect to its contact, an armature pivoted upon the base on an axis common to the axis of the switch arm, said armature "being connected to the switch arm for movement therewith, an electromagnetic coil mounted upon the base on an axis substantially parallel to the base, a holding coil for said armature mounted upon the base on an axis close to and non-perpendicular to the base and in armature attracting opposition with respect to the coil first mentioned, and a normally closed auxiliary contactor switch assemblage comprising contacts mounted upon the armature and holding coil.

3. In an accelerating contactor the combination of an insulation panel, a circuit controlling switch including a contact mounted upon the panel and a switch arm pivoted upon the panel on an axis close to and parallel to the plane of the panel, an armature connected to the switch arm for movement therewith, an electromagnetic coil mounted upon the panel on an axis parallel to the plane thereof for said armature, means normally holding the switch arm open with respect to its contact and with the armature spaced from said coil, a holding coil assemblage mounted upon said panel with the holding coil axis in non-perpendicular relation with respect to the panel, said holding coil working in opposition upon said armature with respect to the first mentioned coil and having an air gap adjusting core, auxiliary contact means carried by said holding coil assemblage, and means carried by said armature for closing a circuit thru the auxiliary contact means when the switch arm is open.

4. In a contactor for the control of electric circuits the combination of a supporting base, a main circuit controlling switch comprising a contact mounted upon the base and a movable contact arm mounted upon the base, an armature connected to said switch arm for movement therewith, an electromagnetic coil mounted upon said base for attraction of the armature to close the switch upon its contact, means normally holding said switch open, a circuit holding coil mounted upon the base having a core in complementary association with said armature but operating in opposition thereupon with respect to the electromagnetic coil first mentioned, and a switch mounted upon said armature and holding coil in normally closed position when the main circuit switch is open.

5. In a circuit controlling contactor the combination of a shallow insulating supporting panel, an L-shaped rocker arm structure, means mounting the rocker arm structure upon a definite pivot axis upon and close to the panel, said rocker arm structure including a switch arm extending substantially parallel to the plane of the panel, a contact at the movable end of the switch arm, a contact mounted upon the panel for the contact of said switch arm, said rocker arm structure having an outstanding armature providing portion transversely disposed with re spect to the switch arm and the plane of the panel, and magnetic coils mounted upon said panel with their axes non-perpendicular to the panel and in axial lines close to the plane of the panel at opposite sides of said armature for selective attraction of the armature by said coils.

6. A contactor as claimed in claim 5 having an auxiliary contactor assembly including contact means carried by one of said coils and contact means carried by said armature in position to close a circuit when the said armature is in at tracted position by said last mentioned coil.

7. In a circuit controlling contactor the combination of a shallow insulating supporting panel, a magnetic coil mounted upon said panel with its axis parallel and close to the plane of the panel, a rocker arm structure pivoted upon a definite pivot axis close to the panel including a switch arm lying substantially parallel to the panel and having also an outstanding armature portion arranged in a plane transverse to the plane of the panel and in position to be attracted by the magnetic coil aforesaid, a holding coil, means mounting the holding coil upon the panel with its axis close to and in acute angled relation with respect to the plane of the panel at the opposite side of the armature with respect to the first mentioned coil and having a contact face arranged to hold the armature in a plane at right angles to the axis of the holding coil when the latter has attracted said armature.

8. In an accelerating contactor the combination of a shallow insulation panel, a main line switch including a stationary contact mounted upon the panel, a switch arm pivoted upon the panel on an axis close to and parallel to the plane of the panel, a contact on the switch arm for engagement with the contact first mentioned, an electromagnetic coil mounted upon the panel on substantially a parallel axis with respect to the plane of the panel, an armature connected to and movable with the switch arm for said electromagnet, a holding coil mounted upon said panel on an axis close to and non perpendicular to the panel at the opposite side of the armature with respect to said electromagnetic coil, and an auxiliary contact assembly including spring actuated contact means carried by said armature and a complementary contact means carried by said holding coil in position to be engaged by the armature auxiliary contact means when the holding coil is attracting said armature.

PAUL V. YINGST.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,106,372 Eisenmann Aug. 11, 1914 1,325,049 Simon Dec. 16, 1919 1,364,944 McInnerney Jan. 11, 1921 1,533,370 Blood Apr. 14, 1925 1,742,875 Quick et al Jan. 7, 1930 1,849,405 McCollum Mar. 15, 1932 1,962,033 Reichold June 5, 1934 2,220,748 Whiting Nov. 5, 1940 2,361,212 King Oct. 24, 1944 2,421,998 Cypser June 10, 1947 

